A variety of devices have been developed over the years to prevent bolts from loosening from whatever they are threaded into and to prevent nuts from loosening from bolts onto which they are threadingly secured.
One example of a bolt lock device is disclosed in U.S. Pat. No. 2,370,223, the disclosure of which is incorporated herein by reference. The device however, is highly complex and requires two counteracting coiled springs in order to provide its locking function.
Examples of nut locking devices such as lock washers having one or more tongues or gripping elements that engage a side of the nut to prevent it from rotating are respectively disclosed in U.S. Pat. Nos. 424,836 and 2,151,919, the disclosures of which are incorporated herein by reference. In the nut lock of the 424,836 patent, the locking tongues would have to be bent outwardly after the nut is secured to the bolt and then forcibly flattened before the nut could be loosened. The locking device in the 2,151,919 patent relies upon friction and may not prevent the nut from loosening under certain circumstances.
Examples of nut locks employing coiled springs are respectively disclosed in U.S. Pat. Nos. 900,589 and 1,763,505, the disclosures of which are incorporated herein by reference. Both however, are highly complex and would not readily lend themselves both as a bolt lock and as a nut lock.